用nodejs访问ActiveX对象，以操作Access数据库为例。

起因有人提问“如果用nodejs访问sql server？” 找了找资料，发现有两类解决方法，使用第三方nodejs插件：https://github.com/orenmazor/node-tds、使用ADODB.ConnectionActiveX对象。参考： http://stackoverflow.com/questions/857670/how-to-connect-to-sql-server-database-from-javascript http://stackoverflow.com/questions/4728385/connecting-to-a-remote-microsoft-sql-server-from-node-js 如果用ActiveX那么在Windows下nodejs将会无所不能，类似写asp。那它们怎么通信？得动手试试经过思路用nodejs通过cscript.exe(windows脚本进程)间接访问ActiveX cscript能解析jscript和vbscript两种脚本，无疑为方便维护选jscript开发。参考：http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/cscript_overview.mspx?mfr=true 需解决的问题 1、跨进程通信新版的nodejs里增加了对子进程的操作，跨进程通信不是问题。 http://nodejs.org/docs/latest/api/all.html#child_Processes 复制代码代码如下: var util = require('util'), exec = require('child_process').exec, child; child = exec('cat *.js bad_file | wc -l', function (error, stdout, stderr) { console.log('stdout: ' + stdout); console.log('stderr: ' + stderr); if (error !== null) { console.log('exec error: ' + error); } }); 如例我们可以拿到控制台的输出内容stdout！ 2、数据库访问相关ActiveX，ADODB.Connection 参考：http://msdn.microsoft.com/en-us/library/windows/desktop/aa746471%28v=vs.85%29.aspx 复制代码代码如下: var connection = new ActiveXObject("ADODB.Connection"); var result = 'ok'; try{ connection.Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + params.accessfile); connection.Execute(params.sql); } catch(ex){ result = ex.message; } return { result: result }; connection.Open(connectionString)，链接字符串参数可以设置访问sql server。参考：http://www.connectionstrings.com/sql-server-2005 3、为方便维护，特别将cscript和nodejs的脚本合并，用typeof exports判断当前运行环境。 4、字符编码cscript代码使用ascii编码非ascii码字符进行“uHHHH”Unicode编码。 5、命令行字符需转义，双引号、百分号在命令行有特殊意义。参数传递使用base64编码，避免冲突 cscript环境MSXML2.DOMDocument可以做base64编解码复制代码代码如下: function base64Decode(base64){ var xmldom = new ActiveXObject("MSXML2.DOMDocument"); var adostream = new ActiveXObject("ADODB.Stream"); var temp = xmldom.createElement("temp"); temp.dataType = "bin.base64"; temp.text = base64; adostream.Charset = "utf-8"; adostream.Type = 1; // 1=adTypeBinary 2=adTypeText adostream.Open(); adostream.Write(temp.nodeTypedValue); adostream.Position = 0; adostream.Type = 2; // 1=adTypeBinary 2=adTypeText var result = adostream.ReadText(-1); // -1=adReadAll adostream.Close(); adostream = null; xmldom = null; return result; } 总结调用流程 1、创建子进程，传递经过编码的参数； 2、子进程处理完毕将数据JSON格式化输出到控制台；（子进程自动结束） 3、读取控制台的数据，执行回调函数。优势 1、使nodejs拥有访问ActiveX对象的能力； 2、实现简单，开发维护方便。劣势 1、只能运行在Windows平台； 2、数据编解码会消耗更多cpu； 3、每次调用需要创建一个子进程重新连接。(可改进) 总结 1、具有一定实用性； 2、跨进程通信性能可继续探索。模块代码：复制代码代码如下: var Access = { create: function(params){ var fso = new ActiveXObject("Scripting.FileSystemObject"); var result = 'ok'; if (!fso.FileExists(params.accessfile)){ var adoxcatalog = new ActiveXObject("ADOX.Catalog"); try { adoxcatalog.Create("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + params.accessfile); } catch(ex) { result = ex.message; return; } adoxcatalog = null; } else { result = 'exists'; } return { result: result }; }, existsTable: function(params){ var connection = new ActiveXObject("ADODB.Connection"); var result = 'ok', exists = false; try{ connection.Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + params.accessfile); var recordset = connection.OpenSchema(20/*adSchemaTables*/); recordset.MoveFirst(); while (!recordset.EOF){ if (recordset("TABLE_TYPE") == "TABLE" && recordset("TABLE_NAME") == params.tablename){ exists = true; break; } recordset.MoveNext(); } recordset.Close(); recordset = null; } catch(ex){ result = ex.message; } return { "result": result, "exists": exists }; }, execute: function(params){ var connection = new ActiveXObject("ADODB.Connection"); var result = 'ok'; try{ connection.Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + params.accessfile); connection.Execute(params.sql); } catch(ex){ result = ex.message; } return { result: result }; }, query: function(params){ var connection = new ActiveXObject("ADODB.Connection"); var result = 'ok', records = []; try{ connection.Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + params.accessfile); var recordset = new ActiveXObject("ADODB.Recordset"); recordset.Open(params.sql, connection); var fields = []; var enumer = new Enumerator(recordset.Fields); for (; !enumer.atEnd(); enumer.moveNext()){ fields.push(enumer.item().name); } recordset.MoveFirst(); while (!recordset.EOF) { var item = {}; for (var i = 0; i < fields.length; i++){ var fieldname = fields[i]; item[fieldname] = recordset(fieldname).value; } records.push(item); recordset.MoveNext(); } recordset.Close(); recordset = null; } catch(ex){ result = ex.message; } return { result: result, records: records }; } }; if (/^u/.test(typeof exports)){ // cscript void function(){ //from http://tangram.baidu.com/api.html#baidu.json var JSON = { stringify: (function () { /** * 字符串处理时需要转义的字符表 * @private */ var escapeMap = { "b": '\b', "t": '\t', "n": '\n', "f": '\f', "r": '\r', '"' : '\"', "\": '\\' }; /** * 字符串序列化 * @private */ function encodeString(source) { if (/["\x00-x1f]/.test(source)) { source = source.replace( /["\x00-x1f]/g, function (match) { var c = escapeMap[match]; if (c) { return c; } c = match.charCodeAt(); return "\u00" + Math.floor(c / 16).toString(16) + (c % 16).toString(16); }); } return '"' + source + '"'; } /** * 数组序列化 * @private */ function encodeArray(source) { var result = ["["], l = source.length, preComma, i, item; for (i = 0; i < l; i++) { item = source[i]; switch (typeof item) { case "undefined": case "function": case "unknown": break; default: if(preComma) { result.push(','); } result.push(JSON.stringify(item)); preComma = 1; } } result.push("]"); return result.join(""); } /** * 处理日期序列化时的补零 * @private */ function pad(source) { return source < 10 ? '0' + source : source; } /** * 日期序列化 * @private */ function encodeDate(source){ return '"' + source.getFullYear() + "-" + pad(source.getMonth() + 1) + "-" + pad(source.getDate()) + "T" + pad(source.getHours()) + ":" + pad(source.getMinutes()) + ":" + pad(source.getSeconds()) + '"'; } return function (value) { switch (typeof value) { case 'undefined': return 'undefined'; case 'number': return isFinite(value) ? String(value) : "null"; case 'string': return encodeString(value).replace(/[^x00-xff]/g, function(all) { return "\u" + (0x10000 + all.charCodeAt(0)).toString(16).substring(1); }); case 'boolean': return String(value); default: if (value === null) { return 'null'; } if (value instanceof Array) { return encodeArray(value); } if (value instanceof Date) { return encodeDate(value); } var result = ['{'], encode = JSON.stringify, preComma, item; for (var key in value) { if (Object.prototype.hasOwnProperty.call(value, key)) { item = value[key]; switch (typeof item) { case 'undefined': case 'unknown': case 'function': break; default: if (preComma) { result.push(','); } preComma = 1; result.push(encode(key) + ':' + encode(item)); } } } result.push('}'); return result.join(''); } }; })(), parse: function (data) { return (new Function("return (" + data + ")"))(); } } //http://blog.csdn.net/cuixiping/article/details/409468 function base64Decode(base64){ var xmldom = new ActiveXObject("MSXML2.DOMDocument"); var adostream = new ActiveXObject("ADODB.Stream"); var temp = xmldom.createElement("temp"); temp.dataType = "bin.base64"; temp.text = base64; adostream.Charset = "utf-8"; adostream.Type = 1; // 1=adTypeBinary 2=adTypeText adostream.Open(); adostream.Write(temp.nodeTypedValue); adostream.Position = 0; adostream.Type = 2; // 1=adTypeBinary 2=adTypeText var result = adostream.ReadText(-1); // -1=adReadAll adostream.Close(); adostream = null; xmldom = null; return result; } WScript.StdOut.Write('<json>'); var method = Access[WScript.Arguments(0)]; var result = null; if (method){ result = method(JSON.parse(base64Decode(WScript.Arguments(1)))); } WScript.StdOut.Write(JSON.stringify(result)); WScript.StdOut.Write('</json>'); }(); } else { // nodejs void function(){ function json4stdout(stdout){ if (!stdout) return; var result = null; String(stdout).replace(/<json>([sS]+)</json>/, function(){ result = JSON.parse(arguments[1]); }); return result; } var util = require('util'), exec = require('child_process').exec; for (var name in Access){ exports[name] = (function(funcname){ return function(params, callback){ console.log([funcname, params]); exec( util.format( 'cscript.exe /e:jscript "%s" %s "%s"', __filename, funcname, (new Buffer(JSON.stringify(params))).toString('base64') ), function (error, stdout, stderr) { if (error != null) { console.log('exec error: ' + error); return; } console.log('stdout: ' + stdout); callback && callback(json4stdout(stdout)); } ); } })(name); } }(); } 调用代码：复制代码代码如下: var access = require('./access.js'); var util = require('util'); var accessfile = 'demo.mdb'; access.create({ accessfile: accessfile }, function(data){ console.log(data); }); access.existsTable({ accessfile: accessfile, tablename: 'demo' }, function(data){ if (data.result == 'ok' && !data.exists){ access.execute({ accessfile: 'demo.mdb', sql: "CREATE TABLE demo(id Counter Primary key, data Text(100))" }); } }); access.execute({ accessfile: 'demo.mdb', sql: util.format("INSERT INTO demo(data) VALUES('zswang 路过！%s')", +new Date) }, function(data){ console.log(data); }); access.query({ accessfile: 'demo.mdb', sql: "SELECT * FROM demo" }, function(data){ console.log(data); }); 最新代码：http://code.google.com/p/nodejs-demo/source/browse/#svn%2Ftrunk%2Fdatabase

　　推荐阅读

　　js汉字排序问题支持中英文混排，兼容各浏览器，包括CHROME

具体技术 1.使用GB编码与UNICODE的转换 2.数组关联排序注意：GB编码库地址 http://demo.jb51.net/jslib/qswhGB2312.js 代码（demo写的很简陋）复制代码代码如下: <script> //power by 毛绒猫猫 liuyutong@baid>>>详细阅读

本文标题：用nodejs访问ActiveX对象，以操作Access数据库为例。

地址：http://www.17bianji.com/kaifa2/JS/23825.html

1/2 1